When a team goes from World Champions to also-rans in the span of several months, there are plenty of culprits and indeed, the 2014 Red Sox have no shortage of players who have underachieved -- from the front office to role players and everyone in between.

Failing grades for the first half are the rule, rather than the exception. A few have performed as hoped and some have even exceeded expectations.

The grades:

POSITION PLAYERSDAVID ORTIZ: B+

Ortiz has twice as many homers as anyone else on the team, and nearly twice as many RBI, so his run production skills remain elite. The big dropoff has come in batting average, where the shift has probably cost him a dozen or so hits.

He's been streakier than usual, but it's easy to think of a half-dozen games the Red Sox won that they wouldn't have won without him. His production is especially impressive when you consider how little thump exists in the lower half of the lineup and the fact that he had to hit without Mike Napoli's protection for three weeks.

MIKE NAPOLI: B-

The finger injury suffered in Chicago in April clearly bothered him for a while as Napoli tried to play through the injury.

He's been more selective than usual with 52 walks in 75 games, in no small part because of the lack of protection behind him the lineup. The slugging percentage is off somewhat, impacted by the finger and other nagging injuries. His defense seems to have slipped at least somewhat from a year ago, when he was cheated out of a Gold Glove, but is still above-average.

DUSTIN PEDROIA: C+

Pedroia's offensive slump a year ago could be attributed to the thumb injury he suffered on Opening Day of 2014, but what is it that explains this season?

In the home opener, Pedroia wrenched his wrist and that may have had an impact on his swing. Whatever the reason, Pedroia's offensive dip has to be a significant concern for the franchise, especially considering that he's signed for seven more seasons after this. At the very least, the fact that his slugging percentage has slipped for a third consecutive year has to be considered alarming.

On the plus side, Pedroia's defense hasn't suffered -- he's played as well at second as he has at any time in his career.

STEPHEN DREW: F

At the time, signing Drew seemed to make some sense. Xander Bogaerts was struggling at short and bringing Drew back would give the Sox a boost against righthanded pitching while stabilizing the middle of the infield.

Drew's defense has been terrific - he's made just two errors in 28 games - and the team's double-play rate has improved since he returned. But at the plate, Drew has been something close to an automatic out. His .487 OPS is something you might see from a National League pitcher.

True, Drew didn't have spring training. But he's been back for almost six weeks and that should have been time enough for him to rediscover his stroke. It hasn't happened.

XANDER BOGAERTS: C-

His first full season has been full of ups and downs. The first few weeks were rocky, with sloppy defensive play at short. Around May 1, he started to hit more like he was expected to, and soon after, his play at short seemed to grow more assured.

By late May, Bogaerts was banging line drives all over the ballpark and having the kind of at-bats that were expected of him. But Drew's return and the subsequent shift back to third base seemed to unnerve him, and his offense soon nose-dived.

Bogaerts then looked uncharacteristically lost at the plate, alternating between chasing pitches out of the strike zone and appearing tentative. There's still time for him to turn it around in the second half, but the first half has been a disappointment.

JONATHAN HERRERA: C-

Herrera found himself in a roster squeeze last week and was optioned to Pawtucket, though it's expected he'll return at some point.

While he was here, Herrera performed the job of utility infielder well enough, contributing at both short and third base on occasion. He didn't provide a great deal at the plate (.233/.307/.289), but then, he wasn't expected to be a thumper.

What Herrera did was fill in well at two infield spots, drop down some well-executed bunts and excel at the proverbual litte things.

BROCK HOLT: A

One of the few pleasant surprises of the season, Holt solved the Red Sox' leadoff vacancy while managing to play seven different positions in the first half, including four (first base and all three outfield spots) that he had never before played professionally.

It's unclear where Holt fits for the future since he doesn't deliver the extra-base power usually associated with corner outfield spots, but given his on-base ability and versatility, the Sox have to find somewhere for him to play.

MIKE CARP: D+

Carp missed an entire month with a stress fracture in his foot and contributed a walk-off hit in the final game of the last homestand of the first half.

But other than that, the highlights have been few and far between for Carp, who stands as something of a symbol for how much things have changed from a year ago. A year ago, he seemed to always be in the middle of a comeback win; this season, there haven't been many of those at all.

JONNY GOMES: C-

The numbers are disappointing, but a closer look reveals that Gomes has, as always, been very good against lefthanded pitching, with an .842 OPS. The problem is, thanks to the underperformance of other outfielders along with injuries, he's actually played more games against righthanded pitching -- and that's where the numbers get dragged down.

Defensively, it may look ugly at times, but Gomes gets to more balls than you'd think -- with the exception of the two lost in the Fenway twilight.

DANIEL NAVA: D

No player has seen a bigger dropoff in performance from last year to this than Nava. In 2013, he got on base, played a better-than-average left field and murdered righthanded pitching. This year, he was twice demoted to Triple A to resdiscover his stroke.

He's been better in the last few weeks, lifting his average from sub-.200 to a slightly more respectable .238 by hitting .315 over his last 17 games. The on-base ability is much improved, but the extra-base power is still nowhere to be found, with a depressed slugging percentage of .310 for the season.

JACKIE BRADLEY JR: C-

First, the good: Bradley's defense has been otherwordly. You might have to go back to Tony Armas or Fred Lynn to find someone who has played center this well, both with the glove and arm. If the first-half is any indication, the Sox have themselves a true Gold Glove-caliber defender.

Now, the bad: the offense. There are positive signs of late. Since the first of this month, when he began to open his stance and change his approach some at the plate, he's hit .375 and lifted his average to a slightly more respectable .227. If Bradley could hit, say, .250-260 and develop enough power to hit a dozen or so homers, he could cement the center field job for the forseeable future.

GRADY SIZEMORE: D+

What seemed like the feel-good story of the spring soon morphed into the harsh reality of the regular season. Sizemore may have overcome a litany of injuries and subsequent surgeries enough to get back on the field and hold up physically, but that was a far cry from being a quality player again.

In time, it became apparent that Sizemore could no longer play center field effectively -- at least not for sustained stretches -- and lacked the power tool he had in his prime. Sizemore deserves a world of credit for his willingness to work so hard for so long, but at this point, he's no more than a fifth outfielder.

A.J. PIERZYNSKI: F

Pierzynski has been gone only a week, but already, the prevailing wisdom has become: what took the Red Sox so long to cut ties? It's difficult to remember much positive impact at all.

He wasn't even adequate behind the plate, which the Red Sox may have feared. But he also wasn't adequate at the plate, which is surely not what they anticiapted when they signed him. He went his last six-plus weeks with the Sox without hitting a homer and his entire last month without a single extra-base hit.

Worse, Pierzynski seemed to operate within his own universe and the overwhelming feeling in the clubhouse was that he was there to enhance his visibility for a future TV gig and one more big paycheck.

Other than that....

DAVID ROSS: D+

Ross hasn't hit much, though it's worth noting that he hit more homers than Pierzynski while they were teammates. But if Pierzynski was everything a teammate shouldn't be, Ross is the polar opposite: committed, competitive and selfless.

His throwing may have diminshed some -- his success at throwing out runners was barely better than Pierzysnki, something that would have seemed unimaginable -- but he runs into the occasional homer and pitchers trust him implicitly. And a better mentor for Christian Vazquez couldn't be found.

Pay no attention to the 9-7 record, which doesn't begin to illustrate how good he's been. With any run support to speak of, Lester would easily have a dozen wins and counting.

His 2.65 ERA is sixth best among American League qualifiers and his 4.62:1 strikeout-to-walk ratio is the best of his career. Lester remains a horse on target for another 200-inning, 30-start season. In curtailing contract talks in spring training, Lester bet on himself as he heads toward free agency, and his stellar first half suggests that bet has already more than paid off.

JOHN LACKEY: B

A three-start skid at the end of June and earlier this month, during which Lackey gave up 16 runs in just 14 innings served to bloat his ERA and blunt his effectiveness. But in general, Lackey has been a dependable innings-eater.

Of his 19 starts, he's given up three runs or fewer 13 times. And 11 times, he's given up two earned runs or fewer. His strikeout-per nine innings (8.0) is the best of his career. He may not be a true ace, but he's as solid as No. 2 as you'll find.

JAKE PEAVY: C-

Peavy seemed primed to enjoy a bounce-back season at the start of the year, but failed to get rewarded despite a number of quality starts. The poor run support continued as Peavy struggled from mid-May through mid-June.

More recently, he's been more consistent and perhaps boosted his own trade value. It's impossible to see him still on the roster come Aug. 1, but he has the respect of the entire clubhouse and has contributed plenty more than the one win his record shows.

CLAY BUCHHOLZ: D-

At this point, it may be prudent to just accept the fact that, for whatever reason, Buchholz is never going to put together a consistent season from start to finish. The good news for the Red Sox is that he appears to have already gotten the poor portion of his season out of the way.

He could hardly be worse than the 7.02 ERA he posted through the end of May. Since returning from a month-long exile to re-jigger his mechanics and approach, Buchholz has pitched more like he's capable. The Sox can only hope that there's plenty more from where that came ahead.

FELIX DOUBRONT: D-

Doubront managed to pitch his way out of the Red Sox rotation, and given the starter depth they have in the minors, may be on his way to pitching himself right out of the organization.

The frustrating thing is Doubront has good enough stuff to regularly be a 12-15 game-winner. But something -- conditioning, shoulder weakness, lack of aggressiveness -- always seems to be getting in the way.

BRANDON WORKMAN: C

Workman's starts have been sporadic, as he finds himself at the mercy of roster manipulations. In eight starts, he gave the Sox a chance in every outing but one and his 1.18 WHIP is impressive.

Over the second half, he'll likely get a regular turn once Peavy is dealt, giving him a leg up on the opportunity to nail down a spot in the rotation next season.

RELIEVERSEDWARD MUJICA: F

What seemed like a solid signing last winter -- with Mujica serving an apprenticeship as eighth-inning set-up man for a year before assuming closer duties next year -- has been a nightmare from the very start.

Mujica's velocity was curiously off in the opening weeks of the season, and even after a gradual up-tick, he's still getting whacked around, with hitters compiling a .319 batting average against him. Whether Mujica's poor first season illustrates just how wide the gulf is between the American League and National League -- he was dominant for much of last season pitching for St. Louis -- is unclear. What is clear is that he's pitched terribly.

CRAIG BRESLOW: D

Breslow has had a long -- if nomadic -- career as a dependable lefty, but something is seriously off this season. It's more than bad luck, too, since he's already walked more hitters this season than he did all of last year.

There were signs of trouble in March, when the Sox mysteriously brought him along slowly. Now, in July, he's a candidate to be designated for assignment soon if he doesn't turn it around.

BURKE BADENHOP: B+

Will the real Burke Badenhop please stand up? After a slow start, Badenhop was nearly perfect for a period of more than two months, going the entire month of May without giving up an earned run. Put another way, Badenhop allowed two runs from April 16 through July 2 during which he made 33 appearances and was scored upon in just three of them.

Three brutal appearances in a row this month, during which he allowed a staggering seven runs while recording just two outs, sent his ERA soaring. But Badenhop has been extremely consistent for the Sox, with a special ability to get double plays with his two-seam fastball.

ANDREW MILLER: B+

On the one hand, Miller does have five losses, with four of them coming in a span of 11 days and each one of them a walk-off loss. On the other hand, Miller has overcome the command issues that plagued him early in his career.

Perhaps he'll never be the closer that some had forecast, but Miller is virtually unhittable for lefties, having struck out almost exactly half of them while allowing them an OBP of .228.

JUNICHI TAZAWA: B

Because he pitches in the shadow of countryman Koji Uehara and doesn't close, Tazawa doesn't get the kind of publicity he deserves. But he's quietly become one of the more dependable set-up men in the game, averaging more than a strikeout per inning and limiting his walks to under two per nine innings.

KOJI UEHARA: A

How consistent has Uehara been? So consistent that it's easy for the casual Red Sox fan to recall his two slips -- one in Oakland and another last week against the White Sox. Every other save opportunity has been converted, and for the record, the two blown saves were games the Red Sox eventually won in the 10th inning.

True, he's more hittable this season, but everything is relative. His WHIP is still a microscopic 0.756 and he's his strikeout-to-walk ratio is a comical 57-6.

CHRIS CAPUANO: D+

Capuano's first month with his (sort of) hometown team must have felt like a dream come true. He made 11 appearances, ranging from one batter to 2 2/3 innings and didn't allow a run. Then, the calendar flipped to May and Capuano's homecoming became more of a nightmare.

Of his last 15 appearances, he was scored upon in more than half and whatever had been working at the start suddenly was not. He went from key bullpen piece to being designated for assignment in what seemed like an instant.

Incomplete: Alex Wilson, Tommy Layne, Rubby De La Rosa

MANAGEMENT

JOHN FARRELL: C-

At times, Farrell has been inconsistent with his game management, including a stretch earlier this year when he seemed to alternate -- sometime inning-to-inning -- between overuse of the sacrifice bunt and abhorring it.

But those are the kinds of curious strategic moves made by desperate managers whose hitters can't buy a hit with runners in scoring position. Farrell has tried everything -- from using six different leadoff hitters to re-arranging the lineup -- with little to show for it.

The team has underachieved in a big way and Farrell has to shoulder some of that blame. But tellingly, effort has not been a question and he's again ensured that the clubhouse has remained a largely positive and supportive environment.

BEN CHERINGTON: D-

After 2012, every move Cherington made seemed to work as designed; this past winter, the results have mostly backfired.

Free agent signings Chris Capuano and A.J. Pierzynski were busts. Worst, Cherington didn't do enough to provide depth at center field and third base, where unproven rookies were being counted on. Finally, the Stephen Drew signing seemed full of panic at the time and hasn't gotten any better over time.

To his credit, Cherington has taken responsibility for the team's nosedive. Having done that, it's his mess to fix.

Sean McAdam serves as Comcast SportsNet's MLB Insider. Read more from Sean here, or follow him on Twitter or Facebook.